620945 has 16 divisors (see below), whose sum is σ = 825552. Its totient is φ = 445440.

The previous prime is 620933. The next prime is 620947. The reversal of 620945 is 549026.

620945 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Cunningham number, because it is equal to 788²+1.

It can be written as a sum of positive squares in 8 ways, for example, as 262144 + 358801 = 512^2 + 599^2 .

It is not a de Polignac number, because 620945 - 2⁴ = 620929 is a prime.

It is a plaindrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (620947) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2549 + ... + 2781.

It is an arithmetic number, because the mean of its divisors is an integer number (51597).

2⁶²⁰⁹⁴⁵ is an apocalyptic number.

620945 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

620945 is a deficient number, since it is larger than the sum of its proper divisors (204607).

620945 is a wasteful number, since it uses less digits than its factorization.

620945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 292.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 620945 is about 788.0006345175. Note that the first 3 decimals coincide. The cubic root of 620945 is about 85.3134905984.

The spelling of 620945 in words is "six hundred twenty thousand, nine hundred forty-five".